Minimally invasive retractor and methods of use

Abstract

A device, system and method for orthopedic spine surgery using a novel screw-based retractor, disclosed herein, that allows for access to the spine through a minimally or less invasive approach. The retractor device is designed as a co-molded part of the tulip of a pedicle screw assembly with opposed arms of the retractor spread apart to open the wound proximally. The arms are removed by separating the arms from the tulip and removing them from the incision. The retractor device is intended to be made of a relatively stiff material, sterile packaged and disposable after one use. A system and method for using the retractor and performing a minimally invasive spine surgical procedure are also disclosed.

What is claimed is: 
     
       1. A surgical retractor comprising:
 a pedicle screw having a tulip including at least one first engagement feature extending proximally from the pedicle screw and from a proximal end of the tulip and at least one second engagement feature extending from a side of the tulip, the at least one first engagement feature having a larger diameter at an end furthest from the tulip than at an end closest to the tulip; and 
 at least one elongate member molded about the at least one of the first and second engagement features such that the at least one elongate member is integrally formed with said tulip, the elongate member being removably affixed to the tulip at a frangible joint. 
 
     
     
       2. The surgical refractor of  claim 1 , wherein the at least one elongate member includes at least one flexible joint region. 
     
     
       3. The surgical refractor of  claim 1 , wherein the at least one second engagement feature is a protrusion extending laterally from the pedicle screw. 
     
     
       4. The surgical retractor of  claim 1 , wherein the tulip is made of metal. 
     
     
       5. The retractor of  claim 2 , wherein the at least one elongate member is made of plastic and surrounds at least a portion of the tulip. 
     
     
       6. The surgical refractor of  claim 1 , wherein the at least one first engagement feature is generally bulb-shaped. 
     
     
       7. A method of performing spine surgery comprising:
 a) providing at least first and second retractor assemblies, each retractor assembly including at least one elongate member flexibly and frangibly attached to a pedicle screw, each elongate member molded to the pedicle screw about at least a pair of protrusions extending vertically therefrom and at least one protrusion extending laterally therefrom such that each elongate member is integrally formed with the pedicle screw; 
 b) securing the pedicle screw of the first retractor assembly to a portion of a first vertebral body; 
 c) retracting tissue using the at least one elongate member of the first retractor assembly; 
 d) securing the pedicle screw of the second retractor assembly to a portion of a second vertebral body; 
 e) retracting tissue using the at least one elongate member of the second retractor assembly; 
 f) inserting a rod between the pedicle screws of the first and second retractor assemblies; 
 g) securing the rod pedicle screws of the first and second retractor assemblies; and 
 h) removing the elongate members from the pedicle screws of the first and second retractor assemblies. 
 
     
     
       8. The method according to  claim 7 , wherein removing includes frangibly breaking the elongate members from the pedicle screws of the first and second retractor assemblies.